Something's gotta give, brother.... Your current workload is grossing under $40 an hour before you pay any expenses... Gotta find a way to get those hours down...
Network marketing. That is my best ROI. Second best is working with other cleaners and taking jobs that they can't get to if they are overloaded and word of mouth advertising of satisfied clients. Third best is a good ranking website. Any kind of print advertising is going to be less ROI but necessary.
Build yourself a free Facebook Business Page to start... Get away from the Google Pay Per Clicks... Build a website or get your website built. Revisit PPC yourself. There are a lot of videos on youtube to show you how to setup a good PPC campaign on Google. Depending on your area you might be looking at a higher rate PPC. In Sacramento, Ca the PPC for "carpet cleaning" (**note the quotation marks**) and [carpet cleaning] was about $14 per click. But if you're somewhere where carpet cleaning isn't competitive the price will be much lower. Before you sign up for PPC make sure you know what you're signing up for...